Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

Annotations already declare read-only, idempotent, open-world, non-destructive, but the description adds real behavioral context beyond them: no auth required, hostname-matched platforms resolve in milliseconds while custom domains take a few seconds because the detector probes well-known endpoints in parallel. It also enumerates the returned fields and explains what archive_method/forward_method and instructions mean downstream.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Front-loaded with purpose, endpoint, and auth model before behavior and return shape, and every sentence carries information. The internal build tag '(Phase 12 Wave 3 W3.1)' and dense parenthetical detail are minor noise for an agent.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

With no output schema, the description usefully enumerates the return fields and their role, plus latency expectations. It leaves the semantics of the confidence value (scale/interpretation) unexplained, a minor gap for a detection tool.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100% for the single url parameter, so the schema already documents it. The description's added detail (any well-formed URL works, hostname-match short-circuits the probe) largely restates what the schema description already says, meeting but not exceeding the baseline.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

States a specific verb+resource (detect the content platform behind a URL) and names the exact endpoint, plus enumerates the detection targets (Substack / Beehiiv / Ghost / Medium / Brevo / custom). It is clearly distinct from siblings like verify_license, lookup_content, and purchase_license.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Gives clear context for use: public no-auth lookup on a publisher URL, returning the onboarding workflow inputs that Opedd's setup wizard consumes. It does not name an alternative tool or state when NOT to use it, so it falls short of explicit routing guidance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.